SCIENCE— ADVERTISEMENTS 



SCHOLARSHIP MAN 



in the physical sciences, with experience in university 

 work, thoroughly familiar with scientific methods and 

 literature, and with knowledge of French, German, 

 Italian and Spanish, desires position with publisher 

 of scientific literature, or in scientific institution. 

 Highest references. Address "J.W.", care "Science," 

 Garrison, N. Y. 



Graduate of the Massachusetts Insti- 

 tute of Technology, and Ph.D. 

 of Johns Hopkins 

 University 



at present assistant processor of organic and physio- 

 logical chemistry and toxicology, desires to hear of a 

 position for teaching. Medical School preferred. 

 Experienced as a teacher and in clinical analysis, and 

 with wide experience in sanitary chemistry and 

 biology, both as a teacher and in practical work. 

 Address S, care Science. 



Archives of Psychology 



RECENT NUMBERS 



19. An Empirical Study of Certain Tests for 

 Individual Differences. Maky Thkodoea Whit- 

 ley. Pp.146. $1.25; cloth, $1.50. 



An experimental testing oJ various tests of memory, 

 association, perception, movement, etc., with indications 

 of the relative value of different forms of test. 



20. Visual Acuity with Lights of Different 

 Colors and Intensities. Dayid Edgab Rice. 

 Pp. 59. 50 cents ; cloth, 75 cents. 



An experimental determination of visual acuity under 

 red, green, blue, and uncolored Illumination, and of the de- 

 pendence of this acuity on intensity of the illumination, test 

 characters, individual differences, and photometric methods 

 employed. 



21. The Curve of Forgetting. C. H. Bban. 



Pp. 45. 45 cents ; cloth, 70 cents. 



A study of the rate at which simple motor acts, sensory 

 impressions, and sensori-motor experiences are forgotten 

 and of the dependence of the curve of forgetting on degree 

 and distribution of learning, on method and material, and 

 on individual diSerences. 



22. The Influence of Caffein on Mental and 

 Motor Efficiency. H. L. Hollikgwoeth. Pp. 

 167. $1.50 ; cloth, $1.75. 



Complete report of an extensive investigation of the in- 

 fluence of caffein on accuracy, speed, and quality of perfor- 

 mance in tests covering a wide range of sensory, motor, and 

 higher mental processes, including also general health and 

 quality and amount of sleep. 



THE SCIENCE PRESS 



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HEARSON 

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With Patent Capsule Tempera- 

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These utensils are widely used in European laboratories 

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We furnish them in nine sizes for gas heating, 

 five sizes for oil heating, six sizes for electric 

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